Grate bar



July 18, 1933.

J. S. THOMPSON GRATE BAR Filed Nov. 1'7, 1931 I INVE 0R ATTORNEYS Patented July l8, 1933 s J MES s. 'rnomrso'n, 'OF NEW ROCHELLE; NEW YoBK,

' narrow, "or: CLEVELANRf OHIO, A CORFQIRATION' or DELAWARE A v Appheatiqu jl ed iwlve b 17,i11931. Seria1 1Y0. 575,535,: 1

Q Thisinvention relates 1 type u mot v q er; har s a d for other. heavy I duty purposesand ,is concerned. more particularly with anovel grate 5 ba l- Which is of extremelylightweight; w

tion. which {add vto the durability .of the; bar

and increase itsv resistance "touidistortion,

Warping, etc, resulting from the temperatures to which itfis exposed in operation 1 p; a

The new-bar comprises a "carrier of any suitable construction prbyided. with trunnions and a shaker arm; and a plurality of fuel-supporting units or fingers mounted de} tachably on the carrier across the latter and free to move angularly relative to the carrier to a limiteolez ztent. These units are of sheet metal and. preferably made of a single steel blank, the latter being shaped by aaseries of forming operations i'tO produce a hollow platelike article having-f a recess :in its bottom, in {which the carrier isreceived and a 7 fuel supporting top. Thetopand side faces of the unit are formedwith.irregularities which prevent cumulative expansion efi'ects and theseirregularities may be socarran'ged as to. provide Wideand uniform distribu? tion of air to the fuel carried by the unit. As a furtherf'feature, theunitis constructed to mak'eit self-cooling by induced circulation of air through its interior and for thislpurpose, the unit is provided with'jopeningsat or near its lower end i which permit cold air from below the gratefto'enterthe interior of the unit, and otheropenings' atia higherlvel through which the" an" may escape; These openings are so formedl and disposed "asto prevent their. being"fclo'gg ed ivith ashes and, as the air from the ash 'pfan flows to the fuel bed, aportion ofitentersthe chamber Within the unitfiie'ar botthn thereofland passes out r near' the top,- fthe ten1perature of the unit causing continuous airflow-through it. The entrancei openi ngs the-unit also act'as a drainageineans for the chamber in iig drawing, in whic being broken away; and;

ns'sicmon TO "FIR BAR coRrog that i h l P is lb i i-b eane ut b hes is @For er uIfierstdDd ngDf he n ention, referencemay behqdt the accompany- Eigis. afr w i l lst a i g were bar in cross sect on with p a fuel supporting; unit thereon shown; n; elevation Y ishoyvniin endelevation] c In the embodiment of thei' time the grate", bar comprise a" carrierw i j i e des a w en; hav ng ,e t upstandin'g. flange l2 upper 1 face and a per lgq #1 16 9??? 2 is a fragmentary vie vv s aportinv of the carrier with: two units thereon st n ni ex nd ial l h under side of the web Thefcarrie'r pro? vide has endswith trunnipn farins ii m I videdWith trunnions l5 and 'the carrier ay be r'ocked on its ,trunnions byasha-ker arni16 ext n ing v nw rd y f o its der. 1 shria,

$ 0 e dap e t b ei i s fi dtoe h k rod by Whicha group'lot carrierv bars in the 'gratemaybe sha en in. unison'f I The fuel is supported onuthe car the top of a plurality of fuel supporting units en ra ly e ign e 17- .L'Eachi f he f t i d bf Sh t t c s chas she tfi el i a relatively light gauge; The units' may be made of; a pair of blanksrproperlyiforined' and provided with defining flanges, the tvvo halvesfoftthe complete unit beingconnected With their flanges in i egis tryp or each unit may bejformed of a singlesheetnietal. blank as d c ib n my ep nd ng. PPl atiQ Ifei l T loiver' edge witharecess'of ashape generally Eachfunit a ullistiafieiisf ill-width its I abovegidenti fied. a The, one pieceunit is preh similar to thecross-section of the carrierfso.

that the unit can beniounted on; the barrier .dgewise, andjtherecess is of somewhatfgreat re rl dimensions than .the earner so that 'the 95 carrierto' a liinited degree Whenthe-carrier unit isffreelto move angularlyrelative ,t jthe is rocked. Ordinarily, the hnit rests'onlthe flat surfa'Ce's IS on Bitl11itl of the flange an he ang l moveme 6f he1 el tive t e-the carrier is lirnitedby engagement i of one or the other of the lugs 19 on the unit at the mouth of the recess With the under side of the web 11. I

The unit illustrated is made of a single blank of sheet metal and it has a solid top which is formed with irregularities which preventthe expansion of the. top from being similarly provided with irregularities to premetal outwardly, and the lugs partly define .a-ii'f passages 21 between them for upward ar'atedfby air channels 24 and air flowing cumulative. The side walls of the unit are vent cumulative expansioneifects and the irregularities in the top and: side walls also stiffen and strengthen these parts.

In the construction shown, the side Walls are'provided with a plurality of vertically extending lugs 20 formed by shaping the flow of airalongthe side faces .of the unit.

Extendingacross'the airpassages are stiifen ing' and strengthening beads. 22, these beads extending; outwardly from the face of the u'nit'a less distance than'th'e lugs 20 and thus not interfering with the upward flow of air between the lugs to a substantial degree.

The top of the unit is provided with a plurality-of small projections 23 which are sepup through the passages 21 enters the chanfuels and is distributed'over the top. of the I I unit to the fuel: supported on the projections.

; 'By fo'rmin the top with afmultiplicity of projections, t is portion of the unit is made strong and rigid and the total expansion of the top from end to end due to the temperature of the fuel bed resting thereon is not cumulative. Some portions of the top expand horizontally while other portions ex- 1 pand in a generally vertical direction and the consequence is that the exposure of the top to working temperatures does not result in the topbecomin warped orbulged.

o Similarly, the formation of the side walls of side walls might bulge and buckle.

the unit with the projections and beads strengthens these walls and permits the unit to be made of lighterstock'. These walls are in compression under the load of the fuel bed when the unitis in service and if it were not for the use of such irregularities, the The strengthening of the side walls of the unit by themeans described also providesfora wide distribution of air to the fuelso that more rapid andcomp'lete combustion is obtained.

.In the one piece unit the side Walls may constitute downward extensions from the top, with each side wall having edge flanges 25'which meet and are joined by a line of welding 26; Where the unit is made of two parts, these parts are preferably ofdish shape and provided with edge flanges which vare placed in contact and then connected bya line of welding.

When the unit is in service the top isi in contact with the burning fuel while'the hott orn hes at a substantial distance below the constructed the 1,918,498 I v V fuel bedand is kept at a much lower temperature thanthetop bythe relatively cold air which is flowing-upward from the ash pan through the grate to the fuel bed. 7 In orderto equalize the temperature within'the 'unit and prevent localizedheating, I have.

new unit so as to "obtain air circulation. b

For this purpose, the unit is provided with air. entrance openings 27' at or near the bottom thereof and air exit openings 28 near the top." The openings 27 are preferably formed along the seam in the lowermost portions of the unit on opposite sides of the recess in' which the carrieris received,flalthough if desired, entrance openings 27 formed inthe substitution for or in combinati'onwith the openings '27.Q'Similarlybpenings '28 are preferably in the edge' of the unit but ifdeopposite faces of {the unit 'may be used in sired the faces of the unitlmay be forrned with openings 28" preferably inthe outer most air channels 21.' Openings 28 and 28 may be used alternatively or in combination. When the openings are formed in the seam,

the two edges of'the blank may bev sh'apedas indicated at 28a, Fig.2, so thatthe openings are completed when theedgesare placed in contact in the shaping operations. The disposition ofthe'openings in'the 'mannerillustrated prevents theopenings from becoming protected by overhanging'portion's of the unit and the openings 28ilying below strengthening ribs 22.

clogged with ashes," the openings 28' being In the'unit constructed as"described,air

flowing up from the ash pan isinduced into the interior of the unit through the bottom openings by the draft through the unit created by the heating of'the top thereof, and

the cold air flows through the central chain her and passes out through the top openings, thence flowing upwardly between the-ends of units on adjacent cross bars to the fuel bed. The'bottom openings, are kept clear of serve for drainage purposes as above pointed out, and since they are inthe lower parts of the unit, water used in cleaningthe ashpan cannot collect and be retained in the unit, What Iclaim is; Q i e 1. A grate bar which comprises a carrier and a 'pluralityofffuel-supporting units- .Inonnted transversely thereon, each unit comprising asheet metal body resting edgewise on thecarrier' and containing a large central chamber, said body having a recess in its lower edge for reception of said carrier and said chamber having an openlngcnear its lower end for admission of. air into said; chamber, and an opening near itsttop for escape of air from said chamber.

2. A grate bar which comprises a carrier and a plurality of fuel-supporting units mounted transversely'thereon, each unit comprising a sheet metal body resting edgewise on the carrier and containing a large central chamber, said body having a recess in its lower edge for reception of said carrier and,

said chamber having an opening in its edge near the bottom of said body for admission of air into said chamber and an opening near its top for escape of air therefrom.

3. A grate bar which comprises a carrier and a plurality of fuel supporting units resting edgewise on said carrier and extending transverse thereto, each unit comprising a body of sheet metal containing a large cen-.

tral chamber and being formed witha recess for reception of said carrier, the body having an edge seam along at least its side and bottom edges, said seam being provided with an opening near the bottom of the chamber for admission of air, and an opening near the top of the chamber for escape of air.

4. In a grate bar, a fuel supporting unit of sheet stock having a recess open at its lower edge for reception of a carrier bar and havmg a central chamber coextenslve w1th said unit, said chamber having an air inlet opening through the chamber wall near the ,bot-

tom. of the unit and an air outlet opening unit, said unit having an opening'inits edge at its lowest point for admission of air into said chamber and an opening in its edge near 1 its top for escape of air from said chamber. 6. In a grate bar, a fuel supporting unit of sheet stock havinga recess for reception of'a carrier bar and having a central chamber co-extensive with said unit, said unit having an edge seam along at least its side and bottom edges formed to provideair opening near the bottom of the unit-for admission of air intosaid chamber and an openingnear the top of the 'unit for escape of air from said chamber.

7, Ina grate .bar, a fuel supportingunit of sheet-stock having a recess for reception of a carrier bar and having a large central chamber, the wall of said-unit having an opening near the-bottom of the unit for admission ofairinto the chamber and an open- 2 ing near the top of theunit for escapeof air e from the chamber.

8. In a grate bar, afuel supporting unit having a recess-in its lower edge for reception ofa carrier bar, said unit being hollow and formed of sheet stock and, having a pair of i openingsin its lowestportionsone on each 1 side of said recess for admission of air: into the hollow interior of the -un1t, and a pair of" openings one on each side of said recess and nearthe top of the unit for escape of air.

9. In, a grate bar, a fuel supporting unit having a recess in its lower edge for reception i of a carrier bar, said unit, being hollow and formed of sheet stock, said unit having a pair.

of openings in its edge inits lowest portions, one opening on each slde, of sald recess, for

admission of air into the interior of said unit, v y

and a pair of openings in itsedge near its top,

one opening on each side of said recess, for

escape of air from the interior of the unit.

"10. A grate bar which comprises a plurality of fuel supporting units, each having an opening for reception of a carrier, and a carrier'rece ved 1n the openingsin 'sald units,

each unitbeing hollow and havingopenings near its bottomon opposite sides of said car rier for admission of air into its interior and openings near its top on opposite sides of said carrier for escape of air. I

11. In a grate bar, a fuel-supporting unit having an opening forreception of a carrier bar, said unit being hollowand having air I a admission openings near its bottom-andfon opposite sldcs of said carrier bar openings,

- and air outlet openings at its top 011 opposite sides of said carrier bar opening.

. JAMES S. THOMPSON. 

